Method of producing a resin



Patented Apr. 18, 1939 METHOD OF PRODUCING A RESIN Howard B. Moore, Dayton, Ohio, assignor, by mesne to New Wrinkle, Inc., Dayton, Ohio, a corporation of Delaware No Drawing. Original application November 30,

1936, Serial No. 113,434. Divided and this application March 29, 1937, Serial No. 133,655

8 Claims. (c1. 26022) My invention relates to varnishes and enamels made therefrom that have the power upon drying by heat of forming an uneven surface of regular pattern.

It is the object of my invention to provide an irregular-surfaced enamel coating which has the following features: I

(a) It has a capacity from to per cent greater covering power than previous irregular surface enamels.

(b) When it comes from the oven, it is immediately hard and tough so that it resists the penetration by a finger nail even when warm, as contrasted with previous enamels that take from a number of hours to several {weeks to adequately harden. I I

(c) The time and temperature of baking this rough surface enamel has been materially lessened, it being possible to bake it for one-half hour at 250 degrees Fahrenheit and secure the same or better result than would be secured by baking two hours at 300 degrees Fahrenheit.

(d) It has improved adhesion to the metal surface to which it is applied.

(e) No priming coats are required prior to applying this enamel as is frequently the case in previous enamels.-

(f) It gives a smooth ornamental appearance while still being much smoother than the previous irregular surface enamels, so that the same effect is acquired without the disadvantage of the collecting of dust and dirt.

(g) It is water resistant and has relatively long life and flexibility, as well as durability.

(h) It permits of a predetermined control of the texture of the finish, its characteristic pattern and depth of its irregularities, and it gives a control so as to produce a predetermined uniformity of pattern.

(i) Thewrinkling is positive and so uniform that it is the same irrespective of the type of surface so that the characteristic irregularities are found in recesses to which the material is applied, as well as upon flat, smooth surfaces.

(9') A very small'qua-ntity, relatively, of drier is required, such as metallic driers, so that the amount of metal can be appreciably reduced in the formula.

(is) The foregoing advantage results in it being possible to store the enamel in bulk before application over long periods of time without premature thickening, precipitation or drying, provided that air is rigorously excluded from contact with the surface of the material in bulk.

(I) An additional feature of this coating is that you do not need to apply it to the same thickness as previous coats in order to secure the result; this is one -of the reasons for increased covering power.

(m) The preoxidation or aeration of theresins 10 from which this enamel is made permits of the elimination of the extended baking periods and high temperatures, and facilitates not only the early hardening but also permits the reduction of metallic driers.

(n) The wrinkle control can be effected by controlling the degree of preoxidation of the resins so that the resins can be taken off at a given point of oxidation in order to control the subsequent product. The viscosities vary according to the 20 degree of preoxidation. The greater the oxidation, the greater the amount of solvent that the product will take and still have the results desired with adequate covering power so that as you increase the oxidation, the cost can be re- 25 duced by increasing the amount of solvent used.

(0) It is an object to produce a coating that is so positive in its irregularities that there are left no fiat or shiny areas known as fish eyes.

(p) This material can be exposed to the air on 30 a surface up to 10 hours without wrinkling and then can be, put into the oven and brought to immediate wrinkling. This enables the'production schedule to be flexible without the necessity of immediately placing the article in an oven as 35 soon as it has been sprayed. This makes it feasible for use in conveyor ovens where there is a gradual increase in temperature in the oven.

(q) When baked in gas-fired ovens, the finish does not crystallize, web, or otherwise show mani- 40 festations characteristic of gas checking, which is an outstanding fault of other types of compositions. This follows directly from the unique method of resin manufacture, a process which completely gas-proofs the frosting oils used.

(r) After spray application, the rate of set-up is so fast, that there is no opportunity for sagging or curtains" to form even'when the work is left permanently in a vertical position.

(8) The wrinkle coatings show a high degree of 50 flexibility which may be increased by the addition of plasticizers, such as tricresyl phosphate, before spray application, so that the coatings may be readily applied to paper, fabrics, rubber, and/or any substratum which may be subjected to bending in use.

Step I--Prepardtion of the grinding vehicle name Phenac or an alkyd resin modified with natural resins and marketed under the name "Teglac. All of the above mentioned synthetic resins are well known commercially and are more fully disclosed in the treatise by Carleton Ellis entitled The Chemistry of Synthetic Resins, volumes I and II, 1935 edition.

The primary resin, as mentioned above, is cooled with glycerol, tung oil and linseed oil fatty acids to disperse the primary resins in order to get clarity of the mixture. This is done at 480 to'495 degrees Fahrenheit for 20 minutes with a slow stream of carbon dioxide gas passing through to retard oxidation and to assist the velocity of they resinification reactions. As a substitute for the tung oil, there can be used any other conjugated double bond vegetable oils such as oiticica I or Scheiber oil or any oil such as linseed whose double bonds have been rearranged to the conjugated position. Also there can be substituted for linseed fatty acids any drying or semi-drying oil fatty acids.

For convenience and because descriptive of the characteristic action, I refer to tung oil and equivalent vegetable oils, or any oil whose double bonds have been rearranged to the conjugated position, as frosting oils, and I refer to the oil fatty acids for convenience as a class as nonfrosting oil acids.

Thereafter I cool the mixture down to 460 degrees Fahrenheit, adding phthalic anhydride' or an equivalent polybasic acid to esterify, that is,

to react with all of the unreaeted hydroiwl groups.

and to bring the acid number down to below 10, still maintaining a slow current of carbon dioxide gas. I now keep the secondary resin so formed at 440 degrees Fahrenheit for about 45 minutes or more. Then this so-called "secondary resin thus formed is thinned so that there is 60 percent solid and 40 per cent solvent, such as toluol, naphtha, or a combination of the two.

This produces a grinding vehicle in which pigments of any color can be ground. The product so far is in paste form and will have a degree of wrinkling power.

Step II-Prepartion of wrinkle synthetic varnish I take the foregoing product and before thinning, allow it tocool gradually to 350 degrees Fahrenheit. When it reaches the temperature of 350 degrees Fahrenheit I then aerate it by submerging in the bottom of the kettle a perforated pipe with concentric rings to which air is supplied at from 20 to 40 pounds per square inch,

increasing the speed of the air or pressure of the air as the contents of the kettle become more viscous. There may be substituted, for the air oxygen or any oxygen-containing gas which is active, as distinguished from inert gases such as nitrogen, carbon dioxide, etc.

The resinous oxidation product thus produced is very nearly saturated with respect to the residual content of ethylenic double bonds still remaining in the polymeric complex. That this process of aeration or air-blowing of the resin actually produces the reaction of oxygen with ethylenic double bonds was confirmed by determinations of the iodine value of the resin before and after aeration. The aerated resins showed a reduction of at least points in the iodine value. .This proves that aeration accomplishes a chemical reaction on a resin. This chemical reaction consists probably in a formation of peroxide linkages at the ethylenic double bonds.

This oxidation can be accelerated by the catalytic action of such products as sodium hydroxide, sodium carbonate, or lead, cobalt, or manganese acetates. In, general it has been found that all monovalent and divalent inorganic salts soluble in the resin mixture are effective in reducing the time required for aeration by one-fifth to onetenth the usual time value.

The viscosity of the mix is preferably that between S-T of the Gardner-Holdt viscosity standards where a sample is dissolved in per cent coal tar solvent and cooled to room temperature. Thereafter I thin with toluol or naphtha, or both, with 40 per cent thinner and per cent solids. This results in a product that is not discolored by oxidation or air blowing. The iodine number is decreased from 30 to 40 units. The product is a wrinkled finish, which can be used clear if desired, that has extraordinary hardness qualities, and high wrinkling power.

In order to control the wrinkling power, there may be added to the last mentioned finish any one of the metallic driers of cobalt, lead or manganese linoleates or naphthenates. The principle is this: the greater the amount of drier, the finer the design of they wrinkle. Also, the higher the evaporation rate of the solvent. the finer the design of the wrinkle.

I have found that a percentage of metal in the drier of A of 1 per cent with reference to the weight of the resin can be used but I prefer A of 1 per cent of metal to the weight of the resin.

Hitherto the method of making a secondary resin of the class described in this disclosure was by adding to the finished oil-modified alkyd the primary resin in various amounts. Veryfrequently, in order to disperse the primary resin in this way it has been necessary to use elevated temperatures, resulting the previously completed alkyd with great danger of gelling the entire mass. Furthermore, in this alternative method of dispersing the primary resin, there is a serious loss of wrinkling power due to overpolymerization which more than of!- sets the increased hardness obtained by this method of incorporation. This method does not ,secure as intimate a chemical reaction or polymerization like the method herein followed, the novel feature of which is the incorporation of the primary resin before completing formation of the conventional old-time alkyd.

One of the new developments according to my method is to first cook the primary resin with the glycerine, tung oil and linseed oil, and then add the phthalic anhydride, instead of the old method of first completing the Glyptal or alkyd resin by cooking phthalic anhydride and glycerine and tung oil together and thereafter adding a primary resin such as the resin modified phenol formaldehyde or alkyd;resin heretofore mentioned. Other types of primary resins may be used as hereinafter specified.

The advantage'of my method is that a funda-. mental chemical combination of the primary resinwith the constituents of the alkyd is actually effected in the act of synthesizing the alkyd, so that eventually a larger and more complex polymeric unit is built up than could possibly be achieved by the old method. This secondary resin-polymeric unit has an independent structure, probably micellar in nature, as contrasted with the colloidal dispersive character of systems composed of primary resins merely dissolved in the alkyds. Clearly, therefore, one obtains a larger and different type of polymeric complex than was possible by following the old method. It is highly probable that the unsymmetrical nature of these secondary resinous aggregates has much to do with mechanical strains set up inthe material on baking, resulting in the distortions known as wrinkling. Essentially my method results in a chemical combination of two or morepolymers as distinguished from a mere physical association as by the previous method. Evidently the older method is no more than a dispersive colloid or solution of the primary resin in the alkyd while my method provides a true new chemical combination of different properties. The unique feature of my invention is the blowing of the resin and the elimination of the blowing of the oil. It would be impossible with my method to employ the blowing of the oil because the air' would be forced out of the mixture due to the high temperatures of cooking employed in making this resin No. 1 or No. 2.

The man who applied the material to a surface, just before he effects the application, controls the irregularity of the resulting surface by introducing the desired amount of drier. That can be done at the plant of the manufacturer applying the coating to his product. The advantage of this product is that it can be made at'the factory of the paint manufacturer and it can be regulated as to its viscosity and its wrinkling power at the plant of the user. By not having any drier in the stock on hand, the paint manufacturer or user does not have to face the loss by undue bodying and skinning in storage.

The following is a more detailed description of my process and product:

It is possible to incorporate any of the foregoing resins, or desirable combinations of them, with the constituents of an alkyd resin in such a manner as to actually enhance the wrinkling power of the alkyd, at the same time gaining superior hardness, quicker drying and better durability characteristic of certain classes of modified alkyds, especially the phenol modified type.

It has been ascertained, by repeated trials, that the procedure disclosed in this invention must be followed in order to react resins of the primary type with the constituents of n alkyd to derive finally a secondary resin of higher and independent' polymeric structure. Essentially this procedure consists in reacting a mixture of vegetable oils and oil acids with glycerine and the primary resin at a temperature of 480 to 495 degrees Fahrenheit for a period of 15 to minutes 'before adding phthalic anhydride and continuing the polymerization at the reduced temperature of 437 to 440 degrees Fahrenheit. The high initial temperature serves to secure complete dispersion of the primary resin with the oils and glycerine so that esteriflcation can be completed advantageously with phthalic anhydride.

Other indices of positive wrinkling action, available with secondary alkyds (in addition to low concentration of catalytic metal required to produce a given effect)- are positive wrinkling response with high pigment concentration and favorable response with high boiling solvents of low evaporating rate.

Composition of m dified alkyd resins Table 1, below, gives preferred compositions of secondary alkyds of progressively increased tendency to wrinkle; other factors, such as drier, solvent combinations, temperatures and time of baking and thickness of film (all of which infiuence wrinkle size) being held constant. The quantities of materials required are placed on a molecular equivalent basis referred to 148 pts. of phthalic anhydride (1 gram equivalent) as standard. The quantity of glycerol required in a composition comprising oils, oil fatty acids, and primary resin is calculated as the total amount necessary to form monoglycerides of the vegetable oil components, the amount to esterify the primary Amberol resin, and, lastly, the quantity required to form a primary alkyd of the structure:

g CHPOzC Otherwise stated, the quantity of glycerol required is calculated from the amount required to esterify all components in the resin, making reasonable assumptions as to the molecular weight of the primary resin. Table 1 consists of a series of modified alkyds, proportions of whose reacting constituents are estimated on the basis of no volatilization losses of glycerine in the cook, the use of tung oil and linseed fatty acids, and the use of a Phenac resin, having an acid number 90 to 107. Phenac is the trade name for a phenol formaldehyde condensation product modified with ester gum, and more fully described in Industrial Engineering Chemistry, 1934, 26, page 714. When no allowance is made for glycerine losses, acid numbers of the final products vary from 10 to 20; this relatively low acid number is itself an indication that the secondary resins obtained constitute actual independent chemical polymers resulting from inner esteriflcation, and not merely physical dispersions of primary resins in the monoglycerides of oils later esterified with unconsumed glycerine and phthalic anhydride.

It will be noted in Table 1 that the proportions of linseed fatty acids is held fairly constantly within the range 7.5 to 10 per cent of the total weight of constituents entering into reaction; it has been found that this small amount of fatty acid reacts more rapidly with glycerine to form monoglycerides than do the oils; this in turn, aids dispersion and esterification of this primary resin within the time limit specified for the cooking at 480 to 495 degrees Fahrenheit. When the linseed acids are replaced by an equivalent quantity of linseed oil, or even tung oil, the time required for dispersion of the resin increases. This shortens the time required to body the resin after adding phthalic anhydride. On. the other hand, if all the oils are replaced by fatty acids, it is impossible to stay on the above cooking schedule unless large quantities of a synthetic resin are replaced by, rosin to inhibit gelation of the fatty acid alkyd.

be adhered to as closely as possible to eliminate variations due to this cause. The working pro- TABL: 1 Secondary alkyd resins of limited polymerization alter esterification with phthalic anhydride Total Grams Grams Grams Grams Total Oil lgth. Resin (trams Perlin- Per- 0. P. For phthalic Perpri- Perperto 148 f No. 23 cent seed cent glyecent anhycant mary cent cant phthalic than:

acids orol drido resin oil anhydride anhydride 45 10. 3 so 1). 5 18 2 148 33. 7 76 17. 1 31. 7 139 51.9 27. 2 40 7. 8 87 16. 9 148 28. 7 100 10. 4 36. 3 182 45. 6 29. 9 40 7. 5 87 16. 3 148 27. 7 100 1B. 7 37. 7 202 44. 0 200 34. 7 90 6. 9 87 15. 1 148 25. 7 I) 17. 4 41. 9 242 40. 8 162 41. 2 41 10. 4 49. 5 12. 6 84 21. 4 56. 6 14. 4 52. 0 361 34 308 40. 5 70 9. 2 90 ll. 8 148 19. 5 146 19. 1 50. 1 381 31. 3 308 34 70 7. 7 90 9. 9 148 16. 3 2H) 32.0 42. 0 381 26. 2 35. 6 45 8. 9 56. 3 11. 1 84 16. 6 140. 5 27. 7 44. 9 401 27. 7

The above series of resinous compositions may be treated collectively since the method of cocking is identical for each. Using solvent combinations that have equivalent evaporation rates, and carefully adjusting the proportions of aromatic and mineral thinners to yield resinous compositions of equal viscosities, plus the same concentration of naphthenate driers (.025% lead and .025% manganese), the foregoing list of compositions shows an increased tendency to wrinkle as the series is ascended. In other words, the number of wrinkles per unit area increases to a maximum, when care is taken to spray samples at the same per cent solids concentration, thus obtaining the same film thickness for comparative samples.

Examination of the speed of air dry showed that the speed-of air dry was proportionate to the phthalic glyceride content; 1. e., resin No. 1 showing the greatest speed (tack-free in 20 minutes) while No. 8 required 70 minutes to become tack-free. Likewise, hardness stood in the same ratio with phthalic glyceride content; independent observations showing that Nos. 1 and 2 were the hardest in the series after a 1-hour bake at 250 degrees Fahrenheit. Neverthles's, a compensating influence with respect to hardness was the higher Phenac resin concentration of Nos. 7 and 8, which equalizes the diminished phthalic glyceride content, so that Nos. '7 and 8 were very nearly equivalent to No. 5 inthis respect. For constant drier concentration (.025 per cent manganese and .025 per cent lead, based on actual per cent catalytic metal referred to the weight of resin). the wrinkle intensity (number per square inch) for constant spraying conditions, increases in the order 1 to 8.

Since the wrinkling phenomenon is the resultant of many factors, such as ratio of fast to slow corporating solvents, solvent retention, temperature of drying, film thickness, many of which it is difficult to arrange in order of their importance, it is manifestly difficult to derive clear correlations of wrinkling behavior with resin composition. No. 1 is lowest in wrinkling power: indeed it is difficult to obtain positive wrinkles with this resin unless fast solvents are used. No. 2 shows an abrupt increase in wrinkling power,

- but does not compare with No. 5, whose rate is most positive in the series. The high proportions of resins in 7 and 8 exert a moderating influence onwrinkle intensity, in spite of the increased oil length (referred to weight of phthalic anhydride) of these resinous compositions.

Since wrinkle formation is sensitive to so many variables, it is desirable that the cooking schedule cedure is to charge the resin kettle with tung oil, linseed fatty acids, glycerine and resin and to raise the temperature as fast as possible to temperatures of 480 to 495 degrees Fahrenheit in the presence of a moderate stream of inert gas (nitrogen, carbondioxide, carbon monoxide, hy-

drogen) maintaining the mix at this temperature for 15 to 25 minutes. The criterion of sumcient reaction is clarity denoted by freedom from oil rings and unreacted primary resin particles,

when small quantities of reacting mixture arev allowed to flow out on tin or glass plates. It is found further that this procedure usually, but

not always, gas-proofs the tung oil present (or other oils subject to gas checking, as oiticica and Scheiber oils). The presence or absence of gaschecking in this connection is of minor significance since subsequent addition of phthalic anhydride, and accompanying polymerization accomplishes this desirable result.

At the conclusion of the 20 minute heating period, the heat source is turned off and the temperature allowed to fall to 460 degrees Fahrenheit. Phthalic anhydride is carefully added over a 10 minute period. It is necessary to increase the heat at this stage to prevent the temperature from falling below 420 degrees Fahrenheit. On adding the last portions of phthalic anhydride, the temperature is raised to 437-440 degrees Fahrenheit and heating continued for a 45 minute period. The mix is then allowed to cool to 2'15 degrees Fahrenheit and appropriate thinners added to produce resin compositions of 60 per cent solids content.

Summing up the foregoing method of preparing secondary or modified alkyds, it is clear that a selective or preferential mode of reacting prical union of the primary resin with glycerol or 0 other constituents of the alkyd, thus leading to heterogeneous, incompatible systems.

Consequently to avoid the development of heterogeneous systems, it is essential that the phthalic anhydride be withheld until later stages of resiniflcation.

The following solvents and combinations of solvents have been most commonly employed, depending on the oil-length of the resin under consideration:

Class I-Resins of high phthalic glyceride content and low oil-length.-These resins, as noted by Examples 1 and 2, require large portions of rich aromatic solvents to insure complete compatibility. The mineral spirits tolerance of these resins is low. A satisfactory formula comprises in parts by weight: Resin 60, benzol or toluol 30, mineral spirits 10.

Class II--Resins of moderately long oil-length (Examples 3, 4, 5) have a much higher mineral spirits tolerance, and may be thinned, as follows, depending on the viscosity desired: Resin 60, solvent naptha 10, toluol 10, mineral spirits 20.

Class [IL-Long oil length resins embracing Examples 6, 7, 8, may be dissolved in any grade of mineral spirits alone providing the resultant viscosity of the 60 per cent resin solution does not surpass workable limits. Hydrogenated solvents are valuable in this connection, since better solvency is secured without too large a viscosity increase.

Concerning toleration limits in viscosity for these secondary alkyd resins, it is advisable tocontrol the addition of mineral spirits or hydrosols in such a manner that the resultant solutions do not exceed S-T on the Gardner-Holdt scale of viscosity standards for varnishes. Viscosities in the higher ranges (V to Z, and Z1 to Z5) require large quantities of thinner in formulations of the enamels in order to obtain satisfactory spraybody consistencies.

It is evident that the secondary alkyd resins, comprising Examples 1 to 8 inclusive, will permit novel solvent combinations to insure a further control over wrinkle pattern, thus supplementing the wrinkling power inheren"; in the materials themselves. By choosing fast solvent combinaticns for the medium oil length resin of Example 2, wrinkling action is obtained very similar in character to that noted when slower solvents are used in thinning resin No. '7.

Experience in formulating has emphasized the desirability of incorporating at least 10 per cent of a moderately fast solvent, similar to naphtha and with fast solvents of the toluol or benzol class in order to secure better spray application conditions. The use of higher boiling materials with slow evaporating rates, in moderate quantity, promotes leveling and absence of orange peel. Terpenic solvents (dipentine, turpentine, and the higher boiling solvents are quite efficient in this regard. The phenomenon of orange peel is a consequence of poor leveling. When noted on wet paint films, the incipient irregularities are very often the cause'of minor changes in wrinkle pattern.

The resins under consideration in Examples 1 to 8 show appreciable sol vent retention properties, especially when the proportions of the more nonvolatile mineral thinners exceed 10 per cent. Solvent retention is usually considered a distinct drawback for air-drying compositions, but in these baking wrinkle-enamels it is a decided asset since it permits large tolerances in working schedules, as denoted by the time that may be permitted to elapse before the work in placed in the oven for baking. This factor is a decided asset in some production schedules.

Ordinarily, these resins may tolerate a 60 min- Extension of wrinkling compositions due to the use of new raw materials (vegetable oils) now being produced in commercial quantities It is understood that this invention is not limited to specific combinations of tung oil and linseed fatty acids as cited in Table 1, but that similar combinations'of other frosting oils such as Scheiber oil (the ester of octadecadienoic-9, 11-

acid 1 with glycerol) and oiticica oil may also be allowed. Indeed, combinations of these frosting oils (in addition to tung oil) with non-frosting oil acids (linseed and Perilla) show the same systematic increase in wrinkling as the series in Table 1 is ascended with respect to oil length. However, when the non-frosting oils (linseed and Perilla) are substituted for the frosting oils, the quantities of frosting oil acids (tung, Scheiber, oiticica acids) are suflicient to insure wrinkling only in the case of Example 1, where 20.5% of fatty acids is specified. From this, it is evident that the frosting oils (oils capable of gas-checking in the oven and of giving an air-dry frost") are much more positive in their wrinkling action than linseed and Perilla oils containing about equal quantities of the glycerides of linolenic and linoleic acids.

Accepted structures of the oil fatty acids themselves may give a clue as to the mechanism of the wrinkling action of these oils. Linoleic acid CH3 (CH2) 4CH=CHCH2CH=CH-(CH2) 1COOH and linolenic acid contain 2 and 3 double bonds respectively, in the isolated position, as contrasted to the frosting oil acids; having double bonds in the conjugated position; namely, elaeostearic acid (alpha form) having the structure octadecadienoic acid -9, ll-acid l (Scheiber acid) having the formula which is dehydrated or dehydroxvlated ricinoleic acid.

(CH3 (CH2) 5-CH(OH) CH2 CH=CH (CH2) '1CO2H and lastly oiticica fatty acids, keto-octadecatrienic acid, with the structure Conjugated systems of double bonds are charac-= terized by rythmic alterations in chain structure as given by the system Manifestly this addition of oxygen to double bonds with this systematic arrangement presents different structural problems than the reaction of oxy en with double bonds in the isolated position, In the latter case peroxide formation is possible, and in the former case the addition of oxygen is complicated by the nearly simul= taneous formation of dimers; for example, the diene polymer produced by heat treatment of oils with conjugated linkages or any conventional drying oil like linseed whose double bonds have been rearranged to the conjugated position.

The combination of conjugated type oils with fatty acids of the .drying and semi-drying type, for example, soya, sunflower, corn, walnut, rapeseed, lumbang, Perilla, linseed whose double bonds are in the isolated position comprise particularly efiicacious compositions for secondary alkyds; but in those cases where extremely coarse wrinkles are required (similar to very long oil length Amberol oleoresinous varnishes) it is desirable to replace oil acids of the linseed type by conjugated oil fatty acids. This augments wrinkling power, although it is necessary to make reductions in the top heat of 480 to 495 degrees Fahrenheit hitherto used to incorporate the primary resin, in order to offset the dangers of coagulation of the resinous mass.

At this point it. is desired to call attention to the fact that any resin in the series 1 to 8 (Table may be blended with any other member; similarly resins made with oiticica or Scheiber oils may be blended with tung oil-linseed fatty acid resins so that any prescribed wrinkle pattern may be obtained. Indeed, the blending of these resins affords endless opportunities for variations in design and textures.

Wrinkle enamels formulated with resins 1 to 8 are usually high in gloss, and those members containing large quantities of oil and Amberol" type primary resins have more luster than the first members of the series (resins 1, 2, and 3). While the substitution of certain natural resins such as fused Congo,il3atu and Kauri have a tendency to reduce gloss, it is frequently more desirable to incorporate the usual flatting agents such as barytes, magnesium carbonate, magnesium silicate, diatomaceous earth, aluminuzn resin. Under this classification comes the Amberol resin heretofore mentioned. It also includes a phenol-formaldehyde condensate dis- I persed in resin and esterified with glycerine such as Phenac resin. Within this class is also included rosin dibasic acid adducts such as rosin maleic adducts esterifled. Also in this class is included ester gum, which is the esteriflcation product of rosin with glycerol. There may be others of this type but these examples are sufficient for the purpose of illustration.

Type 2 in this family of primary resins includes the natural resins which. can be substituted for the synthetic resins heretofore mentioned. Included in this class are the natural resins Congo, Batu, Pontianak, Kauri, rosin, Dammar, Zanzibar, Elemi, Mastic, and East India gum.

Type 3 of this family of primary resins includes the hydrocarbon polymers of the coumeroneindene type. in combination with one of the resins of Type 1.

Type 4 includes the per cent oil-soluble,

This class is advantageously used heat-reactive phenol-formaldehyde condensates. This type is characterized by the fact that it is derived as a reaction product of pure phenol or alkylated phenols with formaldehyde or any aldehyde such as acetaldehyde. For instance, in this type are included para tertiary butyl phenols,

para tertiary amyl phenols; ortho, meta or para cresol; xylenol; para or ortho cyclo-hexyl phenols;

hydroxybiphenyls with formaldehyde.

This type 4 is an oil-soluble and sometimes heat-hardening resin. When incorporated as the primary constituent in a wrinkled resin, they give coatings that are distinguished by their toughness and chemical and alkali resistance. Usually it proves economical to substitute only part of the rosin type of oil-soluble phenolic resin by the 100 per cent phenolic Type 1.

It will be understood that when synthetic resins of the primary type are referred to as a matter of convenience in the claims, nevertheless the substituted natural type indicated in Group or Type 2 may be substituted therefor.

It is desirable to use the synthetic resins because of the accurate control of their character, which is not true of a natural product.

This application covers the method of making the product, while my co-pending application Ser. 113,435, filed November 30, 1936, covers the product. v

This application is a division of my application Ser. No. 113,434, filed November 30, 1936.

It will be understood that I desire to comprehend within my invention such modifications as may be necessary to adapt it to varying conditions and uses.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. Ina method of making a wrinkling resin varnish, mixing vegetable drying oils including tung oil and non-frosting drying oil fatty acids with glycerin and a primary resin of the group consisting of rosin modified and ester gum modifled phenol formaldehyde condensation products, reacting the mixture at a temperautre of from 480 to 495 Fahrenheit for approximatelyiflfteen to twentyflve minutes and thereafter incorporating phthalic anhydride and continuing the polymerization at a temperature of from 437 to 440 Fahrenheit, and thereafter blowing with air to aerate the product.

2. In a method of making a wrinkling resin varnish, reacting a mixture of vegetable drying oils, including tung oil and non-frosting drying ofl fatty acids with glycerin and a primary resin of the group consisting of resin modified and ester gum modified phenol formaldehyde condensation products, reacting the mixture at a temperature of from 480 to 495 Fahrenheit until sumcient reaction produces clarity denoted by freedom from oil rings and unreacted primary resin particles when small quantities of reacting mixture are allowed to flow out on plates, adding phthalic anhydride and continuing the polymerization at a temperature of from 437 to 440 Fahrenheit, and thereafter blowing with air to aerate the product. 1

3. An article of manufacture made in accordance with the method recited in claim 1.

4. An article of manufacture made in accordance with the method recited in claim.

5. In a method of making a wrinkling resin varnish, mixing vegetable drying oils including tung oil and non-frosting drying oil fatty acids with glycerin and a primary resin of the group a age consisting of rosin modified and ester gum modifled phenol formaldehyde condensation products, reacting the mixture at a temperature of from 480 to 495 Fahrenheit for approximately fifteen to twenty-five minutes and thereafter incorporating phthalic anhydride and continuing the polymerization at a temperature of from 437 to 440 Fahrenheitand thereafter aerating the product.

6. In a method of making a wrinkling resin products, reacting the mixture at a temperature of from 480 to 495 Fahrenheit until sufiicient reaction. produces clarity denoted by freedom from oil rings and unreacted primary resin particles when small quantities of reacting mixture are allowed to flow out on plates, adding phthalic anhydride and continuing the polymerization at a temperature of from 437 to 440 Fahrenheit,

and thereafter aerating the product.

'7. An article of manufacture made in accordance with the method recited in claim 5.

8. An article of manufacture made in accordance with the method recited in claim 6.

HOWARD R. MOORE. 

